The compound 4-[[(7R)-8-cyclopentyl-7-ethyl-5,6,7,8-tetrahydro-5-methyl-6-oxo-2-pteridinyl]amino]-3-methoxy-N-(1-methyl-4-piperidinyl)-benzamide as a polo-like kinase (PLK) plays an important part in the regulation of the eukaryotic cell cycle.
The compound 4- [[(7R)-8-cyclopentyl-7-ethyl-5,6,7,8-tetrahydro-5-methyl-6-oxo-2-pteridinyl]amino]-3-methoxy-N-(1-methyl-4-piperidinyl)-benzamide has the structure of the following formula (I).

Similar dihydropteridinones are described in WO 03/020722.